Knife for cutting the points of wire-tacks and nails



Nov. 8, 1927. 1,648,795

J. WIKScH'rROM KNIFE FOR CUTTING THE POINTS OF WIRE TACKS AND NAILS Filed De 30.. 1926 mnney.

Patented Nov. 8, 1927.

UNITED 1,648,795 P ATEN-z'l OFFICE.

.mnozeiwmson rnon', or nossnrnonr, GERMANY.

KNIFE non-Corrine: fliHEZr'oINrs-bsi mam-mm Ann NAILS.

" Application filed December 30,'1926, S na1 Reissues, and'in Germany April 3', 1295.

' ready known, in difierent constructions; I

The essential novelty accordingtothe invention consists inthe peculiar arrangement of several knives at the surface of "a round bar in such a manner that by a rotation of the bar through a. certain angleea'ch time-'- another. knife. may be-brought into the work ing, position, a-free space for the passage of the Wire being each time at. the face of the round: bar opposite the knife. The' cutting edges converging to the center are arranged at av greater distance from each other so that damages of one knife cannot influence the other knives situated at a considerable dis- ..tance which wouldloev the case if the cutting edges would. be close. together.

The cutting edges do not quite meet each other but terminate before their meeting at a depression formed in the center of the round bar, so that in known manner the inserted Wire will not be perfectly cut by'the abutting. cutting edges. The bevel provided in front'of the cutting. edges-onthe onehand and the faces arrangedbetween. the cutting edges on the other hand cause aflongitudina l tensile strain upon the wire whereby the I wire portion .notseparatedlwilll hev pulled off the. wire point. I 2 I By this means further tearing, or longi- ,tudinal. splitting of the wire above. the cutting edges. will be prevented during, the cutting of thepoint even. ifI the material is. too hZU-ICl, too brittle or tends to crack; As in consequence of the splitting the nai'l. head could not.- be pressed. together waste always resulted hitherto. I

All these. draw-backs are. obviated hyjthe new knife and goodsfree of defects. are tained even. if material of'low standard-is used. I II 1 I 4 p In the accompanying drawing apk-nife according to the invention is shown by way of example. 1 is .fro ntelevation of the knife. Fig. 2 shows two knives in section with a piece of wire to be out between them. Fig. 3 is a perspective view of a knife. Fig. 4 illustrates a. piece of cut wire and Fig. 5 is a section taken on line 55 of Fig. 4. In this View the separated nail point is indicated in dotted lines.

Each knife has two cutting edges 1 and 2 converging at an acute angle the roofshaped faces of which extend inwardly" and outwardly. According to the example shown three suchlcutting edge pairs are arranged in regular distance from each other on :the surface of a round bar 7, so thatithere are three knives having the cutting edges 1,

edges 1, 2'. The depression so formed.

serves for the reception of the wire d'to'be cut as sho'wnin Fig.2 and in dotted lines in Fig.1. 1

The center portion eof the round bar-tool 1s hollowed orex'cavated in such a manner thatthediameter of this excavation is. a

little greater than the diameter of the circle n which would lie the points of the convergmg cutting edges 1,. 2;v 1, 2 and 1", 2" respectively of the three knives, so that the two cutting edges ofthe several knivester- 1ninate.,.at the points 3', 4; 3', 41- and 3"". 4 respectively. H j

Atv pointB' the faces a and .0 and at'point 4i. the faces 6 and 0.4" meet and correspond li'ngly at. point S5thefaces 6L and 0., at point 4. thefacesb and ,c, at point 3" the faces a and 0' andat point 4" the faces ZiT' and. c. Inethi's manner a free. space communicating, as shown ,in- Fig. 8, with the excavation e is formed between the points 3, 4.; 8, l and 3", 4" respectively. The centeryline of. the. faces a, 6 between the cutting. edges meets with the excavationfe at a point 5 which lies lower than the points 3 and 4. The points 5" and 5 of the two other l'znives are arranged in the same manner.

The wire portion between the points 3, 5., 4=-will therefore not be influenced by the cutting. edges 1, 2.

' In Fig. 5' the nail point out from'th'e wire is designated 6 whereas 7 and 8 are the flaps between which the faces 9 are lying.

If a piece of wire is inserted between the knives, as shown in Fig. 2. the abutting edges 1 and 2 angularly cut the wire. The portion of the wire lying in between the cutting edges 1, 2 is formed by the faces a, b to the point 6, the center of the wire, that is the middle portion lying between the points 3 and 4, however, still remaining in connection with the cut wire, as the cutting edges do not quite meet each other.

The point 6 is held in the space formed by the faces a, b. The bevel behind the point 5 formed by the excavation e pulls the wire portion carrying the cut out fia s 7, 8 oif the firmly held wire point in the irection of the arrow indicated in Figs. 4; and 5. v The center portion of the wire which is not cut forms a reinforcement preventing the tearing of the wire which otherwise is caused by the outer faces of the cutting edges 1, 2 acting as a wedge when using hard or brittle material. The lateral wedge action is prevented as during cutting the tension is effected by the bevel of the excavation e in.

the direction of the wire, whereby at the same time the flaps 7, 8 are pulled away from the outer faces of the cutting edges 1, 2.

The new knife arrangement also allows the provision of knives of difi'erent shape on one and the same round bar so that by a simple rotation of the round bar one or the other knife construction is caused to be brought in the working position, whereby it is possible, without any difficulty, to manufacture in one and the same machine nails with different shape of points. The change of shape may consist in this that instead of nails having angular points nails provided with rounded points may be made in which case it is only necessary that the faces a and Z2, converging in the example shown under an acute angle, merge into each other so that a semi-circular conical trough'is formed between the cutting edges 1, 2. The length of the nail point also may differently be chosen for the single knives, as, on account of the absolutely independent arrangement of the knives on the face of the round bar and the excavation e in the center portion, it does not matter that for one knife the points 3, 4 and 5 are arranged nearer the center than for another knife.

Instead of three knives as in the example illustrated four and more knives also may be provided whereby it is only necessary that in the extension-line of each knife a free space for the wire is present which results of itself by the outer faces of each knife.

Tofacilitate the adjustment of the knives in their working position the round bar may be provided with flattened portions fitting in correspondingly shaped journals so that on rotating of the bar the cutting edges of the new knife automatically come into the proper position. Notches, holes or the like 9 may also be provided to facilitate the proper selection on turning the bar.

What I claim is:

1. A wire cutting-die comprising a cross seotionally circular rod' having a depressed cross seotionally central portion and provided with a plurality of radially disposed knives formed on one end thereof and recesses formed between each of the knives, said knives having their respective inner ends terminated at points outwardly of said central portion of the rod and each of said recesses lying diametrically opposite its corresponding knife, whereby to permit lateral introduction of a wire over said opposed recesses and their respective knives.

2. A wire cutting die comprising'a cross seotionally circular rod having a depressed cross seotionally central portion and provided with a plurality of radially disposed knives formed on one end thereof and re cesses formed between each of the knives, sai'd knives having each inwardly converging cutting edges and being of substantially V-shaped cross section, the inner ends of the cutting edges of the knives terminating at points outwardly of said central portion of the'rod and each of said knives being arranged substantially intermediately of two of such recesses and diametrically opposite another of the same, whereby to permit lateral introduction of a wire over said opposed recesses and their respective knives.

3. A wire cutting die comprisin a cross seotionally circular rod having a epressed cross seotionally central portion and provided with a plurality ofvradial y disposed knives formed upon one end thereof and a corresponding number of recesses formed be tween each of the same, each of said knives including'relatively opposed inwardly converging cutting edges, the inner ends of which terminate outwardly of said central portion of the rod and said knives being each of substantially V-shaped inwardly converging formation and being arranged substantially diametrically opposite their respective recesses, whereby to permit lateral introduction of a'wire over said opposed recesses and their respective knives.

In testimony whereof I affix my signature.

JAKOB wIKsoHrRoM. 

